Application 6 - Shopping cart

This example suggests how a shopping cart might be implemented.

Application

class Shop(PydanticApplication):
    def add_product_to_shop(
        self, product_id: UUID, name: str, description: str, price: Decimal
    ) -> None:
        try:
            self.save(Product(product_id, name, description, price))
        except IntegrityError:
            raise ProductAlreadyInShopError from None

    def adjust_product_inventory(self, product_id: UUID, adjustment: int) -> None:
        try:
            product: Product = self.repository.get(product_id)
        except AggregateNotFoundError:
            raise ProductNotFoundInShopError from None
        else:
            product.adjust_inventory(adjustment)
            self.save(product)

    def list_products_in_shop(self) -> Sequence[ProductDetails]:
        # TODO: Make this a materialised view.
        return tuple(
            ProductDetails(
                id=product.id,
                name=product.name,
                description=product.description,
                price=product.price,
                inventory=product.inventory,
            )
            for n in self.recorder.select_notifications(
                start=None,
                limit=1000000,
                topics=[get_topic(Product.Created)],
            )
            if (
                product := cast(
                    Product, self.repository.get(cast(UUID, n.originator_id))
                )
            )
        )

    def get_cart_items(self, cart_id: UUID) -> Sequence[CartItem]:
        return tuple(self._get_cart(cart_id).items)

    def add_item_to_cart(
        self,
        cart_id: UUID,
        product_id: UUID,
        name: str,
        description: str,
        price: Decimal,
    ) -> None:
        cart = self._get_cart(cart_id)
        cart.add_item(product_id, name, description, price)
        self.save(cart)

    def remove_item_from_cart(self, cart_id: UUID, product_id: UUID) -> None:
        cart = self._get_cart(cart_id)
        cart.remove_item(product_id)
        self.save(cart)

    def clear_cart(self, cart_id: UUID) -> None:
        cart = self._get_cart(cart_id)
        cart.clear()
        self.save(cart)

    def submit_cart(self, cart_id: UUID) -> None:
        cart = self._get_cart(cart_id)

        # Check inventory.
        requested_products = Counter(i.product_id for i in cart.items)
        for product_id, requested_amount in requested_products.items():
            try:
                product: Product = self.repository.get(product_id)
            except AggregateNotFoundError:
                current_inventory = 0
            else:
                current_inventory = product.inventory

            if current_inventory < requested_amount:
                msg = f"Insufficient inventory for product with ID {product_id}"
                raise InsufficientInventoryError(msg)

        cart.submit()
        self.save(cart)

    def _get_cart(self, cart_id: UUID) -> Cart:
        try:
            return self.repository.get(cart_id)
        except AggregateNotFoundError:
            return Cart(id=cart_id)

class ProductDetails(Immutable):
    id: UUID
    name: str
    description: str
    price: Decimal
    inventory: int

Domain model

class Product(Aggregate):
    def __init__(self, id: UUID, name: str, description: str, price: Decimal):
        self._id = id
        self.name = name
        self.description = description
        self.price = price
        self.inventory = 0

    class InventoryAdjusted(Aggregate.Event):
        adjustment: int

    @event(InventoryAdjusted)
    def adjust_inventory(self, adjustment: int) -> None:
        self.inventory += adjustment

class Cart(Aggregate):
    def __init__(self, id: UUID):
        self._id = id
        self.items: list[CartItem] = []
        self.is_submitted = False

    class ItemAdded(Aggregate.Event):
        product_id: UUID
        name: str
        description: str
        price: Decimal

    class ItemRemoved(Aggregate.Event):
        product_id: UUID

    class Cleared(Aggregate.Event):
        pass

    class Submitted(Aggregate.Event):
        pass

    @event(ItemAdded)
    def add_item(
        self, product_id: UUID, name: str, description: str, price: Decimal
    ) -> None:
        if self.is_submitted:
            raise CartAlreadySubmittedError

        if len(self.items) >= 3:
            raise CartFullError

        self.items.append(
            CartItem(
                product_id=product_id,
                name=name,
                description=description,
                price=price,
            )
        )

    @event(ItemRemoved)
    def remove_item(self, product_id: UUID) -> None:
        if self.is_submitted:
            raise CartAlreadySubmittedError

        for i, item in enumerate(self.items):
            if item.product_id == product_id:
                self.items.pop(i)
                break
        else:
            raise ProductNotInCartError

    @event(Cleared)
    def clear(self) -> None:
        if self.is_submitted:
            raise CartAlreadySubmittedError
        self.items = []

    @event(Submitted)
    def submit(self) -> None:
        if self.is_submitted:
            raise CartAlreadySubmittedError
        self.is_submitted = True

class CartItem(Immutable):
    product_id: UUID
    name: str
    description: str
    price: Decimal

Exceptions

class ProductNotFoundInShopError(Exception):
    pass


class ProductAlreadyInShopError(Exception):
    pass


class CartFullError(Exception):
    pass


class ProductNotInCartError(Exception):
    pass


class InsufficientInventoryError(Exception):
    pass


class CartAlreadySubmittedError(Exception):
    pass

Test

class TestShop(TestCase):
    def test(self) -> None:
        app = Shop()

        product_id1: UUID = uuid4()
        product_id2: UUID = uuid4()
        product_id3: UUID = uuid4()
        product_id4: UUID = uuid4()
        product_id5: UUID = uuid4()

        # Add products to shop.
        app.add_product_to_shop(
            product_id=product_id1,
            name="Coffee",
            description="A very nice coffee",
            price=Decimal("5.99"),
        )

        with self.assertRaises(ProductAlreadyInShopError):
            app.add_product_to_shop(
                product_id=product_id1,
                name="Coffee",
                description="A very nice coffee",
                price=Decimal("5.99"),
            )

        app.add_product_to_shop(
            product_id=product_id2,
            name="Tea",
            description="A very nice tea",
            price=Decimal("3.99"),
        )

        # Adjust product inventory.
        app.adjust_product_inventory(
            product_id=product_id1,
            adjustment=3,
        )

        # Product not in shop.
        with self.assertRaises(ProductNotFoundInShopError):
            app.adjust_product_inventory(
                product_id=product_id3,
                adjustment=1,
            )

        app.add_product_to_shop(
            product_id=product_id3,
            name="Sugar",
            description="A very nice sugar",
            price=Decimal("2.99"),
        )

        app.add_product_to_shop(
            product_id=product_id4,
            name="Milk",
            description="A very nice milk",
            price=Decimal("1.99"),
        )

        # List products.
        products = app.list_products_in_shop()
        self.assertEqual(len(products), 4)
        self.assertEqual(products[0].id, product_id1)
        self.assertEqual(products[0].name, "Coffee")
        self.assertEqual(products[0].description, "A very nice coffee")
        self.assertEqual(products[0].price, Decimal("5.99"))
        self.assertEqual(products[0].inventory, 3)
        self.assertEqual(products[1].id, product_id2)
        self.assertEqual(products[1].name, "Tea")
        self.assertEqual(products[1].description, "A very nice tea")
        self.assertEqual(products[1].price, Decimal("3.99"))
        self.assertEqual(products[1].inventory, 0)
        self.assertEqual(products[2].id, product_id3)
        self.assertEqual(products[2].name, "Sugar")
        self.assertEqual(products[2].description, "A very nice sugar")
        self.assertEqual(products[2].price, Decimal("2.99"))
        self.assertEqual(products[2].inventory, 0)
        self.assertEqual(products[3].id, product_id4)
        self.assertEqual(products[3].name, "Milk")
        self.assertEqual(products[3].description, "A very nice milk")
        self.assertEqual(products[3].price, Decimal("1.99"))
        self.assertEqual(products[3].inventory, 0)

        # Get cart items - should be 0.
        cart_id = uuid4()
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 0)

        # Add item to cart.
        app.add_item_to_cart(
            cart_id=cart_id,
            product_id=product_id1,
            name="Coffee",
            description="A very nice coffee",
            price=Decimal("5.99"),
        )

        # Get cart items - should be 1.
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 1)

        # Check everything is getting serialised and deserialised correctly.
        self.assertEqual(cart_items[0].product_id, product_id1)
        self.assertEqual(cart_items[0].name, "Coffee")
        self.assertEqual(cart_items[0].description, "A very nice coffee")
        self.assertEqual(cart_items[0].price, Decimal("5.99"))

        # Clear cart.
        app.clear_cart(cart_id)

        # Get cart items - should be 0.
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 0)

        # Add item to cart.
        app.add_item_to_cart(
            cart_id=cart_id,
            product_id=product_id1,
            name="Coffee",
            description="A very nice coffee",
            price=Decimal("5.99"),
        )

        # Add item to cart.
        app.add_item_to_cart(
            cart_id=cart_id,
            product_id=product_id2,
            name="Tea",
            description="A very nice tea",
            price=Decimal("3.99"),
        )

        # Get cart items - should be 2.
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 2)
        self.assertEqual(cart_items[0].product_id, product_id1)
        self.assertEqual(cart_items[1].product_id, product_id2)

        # Add item to cart.
        app.add_item_to_cart(
            cart_id=cart_id,
            product_id=product_id3,
            name="Sugar",
            description="A very nice sugar",
            price=Decimal("2.99"),
        )

        # Get cart items - should be 3.
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 3)
        self.assertEqual(cart_items[0].product_id, product_id1)
        self.assertEqual(cart_items[1].product_id, product_id2)
        self.assertEqual(cart_items[2].product_id, product_id3)

        # Cart full error.
        with self.assertRaises(CartFullError):
            app.add_item_to_cart(
                cart_id=cart_id,
                product_id=product_id4,
                name="Milk",
                description="A very nice milk",
                price=Decimal("1.99"),
            )

        # Get cart items - should be 3.
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 3)
        self.assertEqual(cart_items[0].product_id, product_id1)
        self.assertEqual(cart_items[1].product_id, product_id2)
        self.assertEqual(cart_items[2].product_id, product_id3)

        # Remove item from cart.
        app.remove_item_from_cart(
            cart_id=cart_id,
            product_id=product_id2,
        )

        # Get cart items - should be 2.
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 2)
        self.assertEqual(cart_items[0].product_id, product_id1)
        self.assertEqual(cart_items[1].product_id, product_id3)

        # Product not in cart error.
        with self.assertRaises(ProductNotInCartError):
            app.remove_item_from_cart(
                cart_id=cart_id,
                product_id=product_id2,
            )

        # Add item to cart.
        app.add_item_to_cart(
            cart_id=cart_id,
            product_id=product_id5,
            name="Spoon",
            description="A very nice spoon",
            price=Decimal("0.99"),
        )

        # Get cart items - should be 3.
        cart_items = app.get_cart_items(cart_id)
        self.assertEqual(len(cart_items), 3)
        self.assertEqual(cart_items[0].product_id, product_id1)
        self.assertEqual(cart_items[1].product_id, product_id3)
        self.assertEqual(cart_items[2].product_id, product_id5)

        # Insufficient inventory error.
        with self.assertRaises(InsufficientInventoryError):
            app.submit_cart(cart_id)

        # Adjust product inventory.
        app.adjust_product_inventory(
            product_id=product_id3,
            adjustment=3,
        )

        # Insufficient inventory error.
        with self.assertRaises(InsufficientInventoryError):
            app.submit_cart(cart_id)

        # Add item to shop.
        app.add_product_to_shop(
            product_id=product_id5,
            name="Spoon",
            description="A very nice spoon",
            price=Decimal("0.99"),
        )

        # Adjust product inventory.
        app.adjust_product_inventory(
            product_id=product_id5,
            adjustment=3,
        )

        # Submit cart.
        app.submit_cart(cart_id)

        # Cart already submitted.
        with self.assertRaises(CartAlreadySubmittedError):
            app.add_item_to_cart(
                cart_id=cart_id,
                product_id=product_id4,
                name="Milk",
                description="A very nice milk",
                price=Decimal("1.99"),
            )

        with self.assertRaises(CartAlreadySubmittedError):
            app.remove_item_from_cart(
                cart_id=cart_id,
                product_id=product_id1,
            )

        with self.assertRaises(CartAlreadySubmittedError):
            app.clear_cart(
                cart_id=cart_id,
            )

        with self.assertRaises(CartAlreadySubmittedError):
            app.submit_cart(
                cart_id=cart_id,
            )

Code reference

class examples.shopstandard.application.Shop(env: Mapping[str, str] | None = None)

Bases: PydanticApplication

add_product_to_shop(product_id: UUID, name: str, description: str, price: Decimal) → None

adjust_product_inventory(product_id: UUID, adjustment: int) → None

list_products_in_shop() → Sequence[ProductDetails]

get_cart_items(cart_id: UUID) → Sequence[CartItem]

add_item_to_cart(cart_id: UUID, product_id: UUID, name: str, description: str, price: Decimal) → None

remove_item_from_cart(cart_id: UUID, product_id: UUID) → None

clear_cart(cart_id: UUID) → None

submit_cart(cart_id: UUID) → None

name = 'Shop'

class examples.shopstandard.domain.ProductDetails(*, id: UUID, name: str, description: str, price: Decimal, inventory: int)

Bases: Immutable

id: UUID

name: str

description: str

price: Decimal

inventory: int

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'description': FieldInfo(annotation=str, required=True), 'id': FieldInfo(annotation=UUID, required=True), 'inventory': FieldInfo(annotation=int, required=True), 'name': FieldInfo(annotation=str, required=True), 'price': FieldInfo(annotation=Decimal, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

class examples.shopstandard.domain.Product(*args: Any, **kwargs: Any)

Bases: Aggregate

__init__(id: UUID, name: str, description: str, price: Decimal)

class InventoryAdjusted(*, originator_id: UUID, originator_version: int, timestamp: datetime, adjustment: int)

Bases: DecoratorEvent, InventoryAdjusted

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'adjustment': FieldInfo(annotation=int, required=True), 'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

adjust_inventory = <eventsourcing.domain.UnboundCommandMethodDecorator object>

class Created(*, originator_id: UUID, originator_version: int, timestamp: datetime, originator_topic: str, name: str, description: str, price: Decimal)

Bases: Created, Event

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'description': FieldInfo(annotation=str, required=True), 'name': FieldInfo(annotation=str, required=True), 'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_topic': FieldInfo(annotation=str, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'price': FieldInfo(annotation=Decimal, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

originator_id_type

alias of UUID

name: str

description: str

price: Decimal

class Event(*, originator_id: UUID, originator_version: int, timestamp: datetime)

Bases: Event

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

originator_id_type

alias of UUID

class examples.shopstandard.domain.CartItem(*, product_id: UUID, name: str, description: str, price: Decimal)

Bases: Immutable

product_id: UUID

name: str

description: str

price: Decimal

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'description': FieldInfo(annotation=str, required=True), 'name': FieldInfo(annotation=str, required=True), 'price': FieldInfo(annotation=Decimal, required=True), 'product_id': FieldInfo(annotation=UUID, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

class examples.shopstandard.domain.Cart(*args: Any, **kwargs: Any)

Bases: Aggregate

__init__(id: UUID)

class ItemAdded(*, originator_id: UUID, originator_version: int, timestamp: datetime, product_id: UUID, name: str, description: str, price: Decimal)

Bases: DecoratorEvent, ItemAdded

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'description': FieldInfo(annotation=str, required=True), 'name': FieldInfo(annotation=str, required=True), 'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'price': FieldInfo(annotation=Decimal, required=True), 'product_id': FieldInfo(annotation=UUID, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

class ItemRemoved(*, originator_id: UUID, originator_version: int, timestamp: datetime, product_id: UUID)

Bases: DecoratorEvent, ItemRemoved

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'product_id': FieldInfo(annotation=UUID, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

class Cleared(*, originator_id: UUID, originator_version: int, timestamp: datetime)

Bases: DecoratorEvent, Cleared

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

class Submitted(*, originator_id: UUID, originator_version: int, timestamp: datetime)

Bases: DecoratorEvent, Submitted

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

add_item = <eventsourcing.domain.UnboundCommandMethodDecorator object>

remove_item = <eventsourcing.domain.UnboundCommandMethodDecorator object>

clear = <eventsourcing.domain.UnboundCommandMethodDecorator object>

submit = <eventsourcing.domain.UnboundCommandMethodDecorator object>

class Created(*, originator_id: UUID, originator_version: int, timestamp: datetime, originator_topic: str)

Bases: Created, Event

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_topic': FieldInfo(annotation=str, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

originator_id_type

alias of UUID

class Event(*, originator_id: UUID, originator_version: int, timestamp: datetime)

Bases: Event

model_computed_fields: ClassVar[Dict[str, ComputedFieldInfo]] = {}

A dictionary of computed field names and their corresponding ComputedFieldInfo objects.

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'frozen': True}

Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

model_fields: ClassVar[Dict[str, FieldInfo]] = {'originator_id': FieldInfo(annotation=UUID, required=True), 'originator_version': FieldInfo(annotation=int, required=True), 'timestamp': FieldInfo(annotation=datetime, required=True)}

Metadata about the fields defined on the model, mapping of field names to [FieldInfo][pydantic.fields.FieldInfo] objects.

This replaces Model.__fields__ from Pydantic V1.

originator_id_type

alias of UUID

exception examples.shopstandard.exceptions.ProductNotFoundInShopError

Bases: Exception

exception examples.shopstandard.exceptions.ProductAlreadyInShopError

Bases: Exception

exception examples.shopstandard.exceptions.CartFullError

Bases: Exception

exception examples.shopstandard.exceptions.ProductNotInCartError

Bases: Exception

exception examples.shopstandard.exceptions.InsufficientInventoryError

Bases: Exception

exception examples.shopstandard.exceptions.CartAlreadySubmittedError

Bases: Exception